Add support for step models?

[TurBoss]

Hello

it would be very cool to have support to open step models

this can be done with OCE its only an idea

Thanks

[sumpfralle]

Another import format would surely be a good thing.

Anyone interested in this feature may want to take a look at pycam/Importers/STLImporter.py. Basically you only need to create a function that receives a file-like handle and returns a mesh model (made of triangles). Afterwards you can add this new importer function to the list of handled import formats in pycam/Importers/__init__.py. Now it should be available everywhere in pycam.

Pull requests are welcome!

[TurBoss]

Investigating pythonocc-core to see if I can do something... I can't promise anything :D

[TurBoss]

well did a bit of research and found that I'm not able to accomplish this task :D

[sumpfralle]

What a pity!

Out of curiosity: is the step format too complicated or incompatible with a triangle-mesh-based data structure? Or do you think that you currently lack the python skills? (I am not trying to persuade you - I just want to prepare a good starting point for people coming back to this topic later on)

[TurBoss]

Hi

its not triangle oriented example: a curve is not composed of a lot of vertices is just a curve

I'm lacking python and opencascade skills

what I have looked at is: https://github.com/tpaviot/oce https://github.com/tpaviot/pythonocc-core

http://www.pythonocc.org/

will spend some time on this :D

Edit: what most problemd gived to me was the pythonocc installation (didn't manage how to) with conda that seems the only way ... not sure sorry

[TurBoss]

here is an example of a step model: http://www.pythonocc.org/quick-examples/step-ap203-import/

[sumpfralle]

Maybe pythonocc can export a model to STL? This would be the most straight-forward approach for importing step files into pycam.

[TurBoss]

stl still a mesh based format not a cad model I can export in stl from freecad

[sumpfralle]

stl still a mesh based format not a cad model

Yes, indeed. Pycam uses triangle meshs internally for 3D models. Thus this no problem. I assumed that you were contemplating toolpath generation based on 3D models loaded from step files, right? Or did have something else in mind?

I can export in stl from freecad

If freecad supports a non-interactive conversion from step to stl, then this could be a simple option, too. You could take a look at pycam's PSImporter - it uses inkscape for converting (e)ps files to DXF (which can be parsed by pycam).

[palmerr23]

Moving between the two CAD modeling schemes IGES and STEP is a non-trivial issue and has been discussed extensively in CAD forums and there are several (at least partly) successful translation options, most using CAD software that reads/writes both types of model.

I've found that FreeCAD does the trick... most of the time.